Doc is right, a kennel run is best if you can't be with him constantly, training gets my vote though. I live in a small town with a small (29' X 110' ) yard, while my dog is never left unattended we can soetimes be distracted by certain things. He has in these moments crossed property lines buthe has been trained to come immediately when I call. 4 years i'vehad him he has not run frumme.I have no fence, no underground fencing yet he has never roamed farther than the neighbor to either side of my property. This is due to the training he received when he came to live here. that traing used a small innoteck electrical collar, a very long peice of check cord, and a very firm " NO" from me. You might want to try an underground fence. Some people around here have them and they swear by them. Whatever you do be consistent in the training and all will be well